Between 2001 and 2006, NBC's "Fear Factor" pitted teams of contestants against their worst fears -- from heights to speed to creepy-crawlies -- in hopes of claiming a $50,000 top prize.

On Monday, Dec. 12, almost six years after it went off the air, "Fear Factor" returns to the NBC schedule for a run of new episodes. Some things haven't changed, such as host Joe Rogan and executive producers Matt Kunitz ("Wipeout") and David A. Hurwitz ("American Gladiators"), but other things have.

"NBC said to us," explains Kunitz, calling in from the "Wipeout" ranch (which was, and is again, the setting for much of "Fear Factor"), " 'If you're going to bring the show back, it has to be bigger and badder and grosser than ever before.' I think we lived up to that request."

Each episode features four teams of two -- which may be spouses, family members, co-workers, friends, etc. -- facing challenges that test their courage, resolve and intestinal fortitude.

The team that survives each round and completes the final challenge again wins $50,000.

"We have always needed catharsis," Rogan says over coffee at a Hollywood deli. "The time is right nostalgically. A lot of people look back, go, 'Awww, that show was good. What happened to that show?' Then you hear about it coming back. My Twitter is flooded with people since the commercials started to air."

"It was surreal for all of us," says Kunitz, "when we showed up the first day to start shooting. It literally felt like we had gone away for a few months' hiatus and came back.

"On the first day of shooting, we were like, 'This is so bizarre.' We just fell right into it. It was six years since we had shot that last episode, but it felt like it had been six weeks. We were shooting 'Wipeout' and 'Fear Factor' concurrently. At one point, we were shooting 'Wipeout,' 'Fear Factor' and '101 Ways to Leave a Game Show' at the same time. It was a tough summer for me.

"This ranch has a great look. Before it was the 'Wipeout' ranch, it was the 'Fear Factor' ranch. So we love it here."Kunitz wanted to make sure that whatever changed, he still had Rogan at the helm.

"He came back a better host than he ever was," Kunitz says. "He was so present in the scenes we just shot, so involved. It's rare. I can't think of any show where the host is right there when they're doing a challenge.

"He's screaming and yelling and cheering for them. If they're struggling, he's in their ear, and he's encouraging them."

While the stunts and the challenges will be bigger and more elaborate, some of the contestants might not be quite so chiseled as in the past.

"We cast it a little differently this year," Kunitz says. "This is something I learned from 'Wipeout.' If you looked at previous episodes of 'Fear Factor,' they were all just hard-bodies, hard-body guys and hard-body girls, and we broadened our casting base this year.

"Absolutely the hard-bodies are there, but we wanted it to be more relatable. There were a significant amount of pairs that are not your typical hard-body, that are more relatable. The average person sitting at home watching 'Fear Factor' doesn't have ripped six-pack abs. They don't need to be.

"People like to see sexy bodies on TV, so we will have those, but I do feel that we've really expanded our base."

'Fear Factor' is a lot more intense," Rogan says. "It's bigger and crazier than ever before. So if you want to watch it, this is the season to do it, for sure. There are a lot of good characters on, too, a lot of crazy people."

The show has also benefited from advances in filmmaking technology.

"They really didn't have HD when we were shooting 'Fear Factor' before," Kunitz says. "The camera technology has come significantly farther in the years. Back when we were shooting it originally, we'd have three or four point-of-view cameras on a stunt. Now we can have as much as 30 POV cameras on a spot.

"They're those little teeny cameras the size of your palm that can go on a helmet or on your chest, can go underneath the carriage of a car or on the wheel of the train, and give you those crazy shots that really put the viewer right in the moment."

And there's one stunt that even gives Kunitz shivers."If you're worried about gross," he says, "this season is not going to be for you. We have one stunt that's so disgusting and so horrific, that we've questioned whether it's even airable. I can't tell you what it is, but I can tell you that much.